Manufacture of glucose.



CHESTER B. DURYEA, OF CARDINAL, ONTARIO, CANADA.

MANUFACTURE OF eLocosE.

Specification of Letters Patent.

. Patented March 30, 1909.

Application filed March 20, 1907. Serial No. 863,447.

To all whom it may concern:

Be it known that I, OHESTER B. DURYEA, a citizen of the United States,and resident of Cardinal, in the county of Grenville, Province ofOntario, Canada, have invented a new. and useful Manufacture of Glucose,

of which the following is a specification.

My present invention relates to the manufacture of glucose with theobject of providing for the manufacture of the hi hest possible gradesofsaccharification products I which, under commercial conditions, starchand starchy materials are ca able of yielding by means of acid hydroysis. Heretofore, (with special reference to starch from maize) therelative amounts and character of the nitrogenous impurities associatedwith theunmodified green starch converted a have been very seriousobstacles in the way of producin glucose of eminent quality. Moreover, te employment of ordinary thick boiling starch as the saccharificationbase, necessarily involves very irrational conversion details. At theinitial concentrationrequired such unmodified starches yield pastes soexcessively viscous and even doughy, that introduction under convertingconditions must be gradual, i. 6., little by little continuously and ata rate no reater than that which will permit the flu1dification of thestarch milk preceding, before that following gelatinizes. Not only this,but as an additional necessary aid' to the introduction of the charge,it is customary to have all of the converting acid in the converterboiling and in a relatively concentrated state before and during thegradual running in of thestarch milk, as hereinbefore described. Thisabnormal method of conversion results in over, under and mean conversionproducts, in part to an extent which may be represented by a relationwhich the time of introduction of a charge of starch bears to the subseuent time of conversion on a basis of equa temperature throughout, andin part to the extent of retrogressive overconversion resulting from theexcessive strength of the acid at the beginning and up to the time ofcomplete introduction of the charge. The overconversion affects bothcarbohydrates and proteins leading in the case of the formerto theformation of reversion and torrefication prod acts (for instance,so-called gallisin and caramel, respectively), and as regards theproteins to the excessive development of very soluble substancesincluding aminoacids, all of which, notwithstandin elaborate and veryexpensive refining, largely remain in the finished products to theirserious detriment. Further, because of the use of unmodified starch withits associated impurities relatively large proportions of acid areneeded for conversion and as the present general practice is to usehydrochloric acid for this purpose an undesirably large percentage ofneutralization product (common salt) is found in the glucose. Theirrational raw material and associated conversion 'method haveadditional disadvantages.

My new process maybe briefly described as follows Ordinary green starchis modified by subjecting the granules at sub-gelatinizing temperaturesto limited acid hydrolysis. See my United States Letters Patent No.675822, granted to me June 4, 1901. This treatment, in addition torendering the starch potentially thinner boiling to the requisite extentwithout serious carbohydrate loss, also affects the proteins hydrolyzingthem in part to soluble products easily separable from the modifiedgranules by means of simple washing, and concurrently, the nitrogenousbodies more resistant to acid hydrolysis, still remaining insoluble havebeen brought into a physical condition very favorable to theirseparation from the starch granules now free swimming iii the generalmenstruum. This separation may be effected by means of subjecting themodified starch charges greatly diluted with water to the well knowntreatment of passing over starchhouse tables or runs. The tablingprocess simultaneously also brings about a great reduction in the amountof soluble nitrogenous matter in relation to the weight of the starch.The suitably modified starch is now so thin boiling that a normalconversion is practicable. That is, the starch milk for a conversioncharge may be acidified and gelatinized en masse and thesaccharification conversion started and completed in such wise that allof the starch, the remaining impurities and their progressivedecomposition products shall be subjected to hydrolyzing influences forthe same length of time concurrently and homogeneously. Moreover,because of the modification of the starch and its peculiar purityrelatively mild converting conditions are sufiicient forsaccharification requirement-s, additional advantages leading to greatorganic and inorganic purity of the finished products through simple andeconomical refining means.

For comparison, the difi'erences in the steps between the old and thenew processes, may be summarized thus Oldlroccss. h'ewlroccs-s. 1. Crudebase. 1. Crude base. 2. Conversion. 2. Modification of base. (Abnormal).3. Refining.

3. Neutralization. 4. Conversion. 4. Refining. (Normal). (Extravagant).5. Neutralization.

5. Concentration. 6. Refining. '6. Product. (Economical).

(Indifferent purity). 7. Concentration.

8. Product.

(Super-pu rity) In practice, operating upon maize starch for example andbeginnmg from the deposition of crude starch upon the primary runs ortables my procedure may be stated as follows :The crude base is modifiedby means of acid hydrolysis (see my U. S. Patent N 0. 675822), at agravlty of about 20 Baum or somewhat higher. Purification follows,preferably by means of dilution and retablin at a gravity of about 4Baum, as herein efore described. The extent of the modification mayadvantageously be such that when the now artificially thin-boilingstarch granules are incorporated with water so as to form a suspensionof about 16 Baum, the application of gelatinizing temperature will yieldpastes or semi-solutions so moderate in viscosity that masses thereofmay be eflectively stirred or agltated mechanically on a practicalglucose scale. Charges of such suspended starch having incorporatedtherewith suitable acid of an appropriate strength, for instance,hydrochloric acid of about 0.05% by weight onthetotal water present, areconverted referably normally or en masse under a out.

thirty pounds steam pressure and temperature for about thirty minutesdepending upon the extent of the saccharification desired. It isadvantageous to acidify the suspended starch in a special tank providedwith an agitator and also to raise the temperature therein afteracidification to nearly the gelatinization point (by means of closedcoils) before introduction into the converter. The process may be thenproceeded with in a converter of the usual type in which case a portionof the water necessary to provide for the desired gravity of the lightliquors, reserved for the purpose from the starch suspension hereinabovereferred to, is introduced therein and boiled. The'hot acidified starchcharge may then be rapidly introduced at atmospheric pressure whileboiling is maintained. As soon as the charge is in, the pressure israised, the conversion completed and the charge blown out into theneutralizer. A more strictly normal conversion, however, may beconducted in a converter furnished with internal agitators. Inconnection with this, the suspended izing the charge and finally refininstarch is introduced before gelatinization. The agitators need beoperated only briefly during the beginning of the conversion, 2'. 6.until the granules have become gelantinized and the charge freely fluid.Or, the old type of converter may be used and the acidified suspendedcharge gelatinized and even heated to boiling in the auxiliary agitatorand closed coil heating tank heretofore mentioned, before transferringto the empty converter and placing under main saccharificationconditions. lnherently, the two latter methods require a somewhat higherpreliminary starch modification than the first. After saccharification,the charges may be neutralized in the customary manner, filter pressedand the resulting light liquors of unparalleled purity and generalexcellence may be refined and concentrated at reduced expense by wellknown and established ways and means.

What I claim is 1. The'process of manufacturing glucose consisting inproviding thin boiling or modified starch by acid hydrolysis, at agravity of about 20 Baum, and at a temperature of about 55 C. wherebythe impurities are in a state to be readily separated from the starch;separatin the'impurities from the modified starch, for instance, bysubjecting the starch charges diluted with water to about 4 Baum to thewell known treat ment of passing over starch-house tables, or runs;converting the purified, modified starch, in suspension with water at agravity of about 16 Baum, by rendering it acid,- for instance,hydrochloric acid in the proportion of about 0.05% by weight on thetotal water presentand submitting it to about 30 lbs. steam pressure forabout thirty minutes; neutralizing the charge and finally refining andconcentrating the product.

2. The process of manufacturing glucose consisting/in providing thinboiling or modified starch by acid hydrolysis at an elevated temperaturewhereby the impurities are in a state to be readily separated from thestarch; separating the impurities from the modified starch; convertingthe purified, modified starch suspended in water by rendering it acidand submitting it to an elevated temperature under pressure; neutralandconcentrating the product, substantia ly as specified.

3. The process of manufacturing glucose consisting in providing a thinboiling or modified starch of a definite character in a which theimpurities are in a state to be readily separated from the starch,separating the impurities from the modified starch; converting thepurified, modified starch by heating with dilute acid so that in themain converting influences act concurrently and uniformly throughout theentire mass and finally neutralizing, refining and concenifzfaating theproduct,'substan tially as speci- 4. The process of manufacturingglucose consisting in providing a thin boiling or modified starch, byacid hydrolysis, at a high specific gravity and elevated temperature inwhich the impurities are in a state to be readily separated from thestarch; separating the impurities from the modified starch; convertingthe purified, modified starch by heating it With dilute acid underpressure so that in the main converting influences act concurrently anduniformly throughout the entire mass and finally neu- 5 tralizing,refinin and concentrating the product, substantially as specified.

In testimony, that I claim the foregoing as my invention, I have signedmy name in presence of two Witnesses, this 15th day of 20 March, 1907.

' CHESTER B. DURYEA.

Witnesses:

C. S. SUNDGREN, HENRY THIEME.

